Top roll for drafting mechanism



April 21, 1953 K. BUTLER 2,635,300

TOP ROLL FOR DRAFTING MECHANISM Filed Sept. 2, 1949 FIE-J IN VEN TOR.

WKM, WKW,

ATTY.

' spite of the proven advantages of Patented Apr. 21, 1953 TOP ROLL FDR DRAFTING MECHANISM Richard K. Butler, Whitman, Mass asslgnor, by I mesne assignments, to Textile Engineering Corporatlon, Whi

Massachusetts tman, Mass, a corporation of Application September a, 1849, Serial No. 113,795 6 (Cl. 19-142) This invention relates in general to drawing rolls for drafting textile fibers, and in particular to top rolls of the ball bearing type commonly known as anti-friction top rolls.

This type of top roll, in which the shell rolls bearing the cots are supported on ball bearings for rotation about a non-rotative shaft positioned in the cap bars of the yam-drafting assembly, has numerous welt-known advantages over both the solid type of top rolls and the shell type rolls using plain bearing as in the matters of saving of time and effort and consequent expense of frequent lubrication, avoiding the escape of liibri- I cant onto the cots and the stock being drawn, steadier running and hence better work, elimination of frequent cleaning, and other recognized virtues.

The object of the present invention is to provide a top roll of the double-boss type equipped with'ball bearings, which will be capable of rendering long and satisfactory service in situations where heavy loading of the top rolls is compelled by the nature of the material being drawn, or by the d i and manner of operation of the particular drafting system in which it is employed,

7 and where also as a further condition of use the maximum outside diameter of the cot or fiberengaging surface is limited. This latter factor of limitation on the outside diameter of the cot has heretofore limited the size and hence the load-bearing capacity of the ball bearings, and hence has restricted the use of anti-friction top rolls to cases where only relatively light loading has been required. This is because the cot must have sufiicient thickness in its walls to meet the requirements of resilience for proper drafting, and so its internal diameter cannot be materially increased at the expense of reduced wall thickness in order to accommodate a shell roll of greater diameter capable of admitting a bearing of sufficiently increased size to carry the load of the extreme roll weighting met with in certain instances. Similarly, a reduction in the shaft diameter to accommodate a larger capacity ball bearing is impracticable because of the resultant increased degree of bending of the shaft under the heavy burden, which lifts the free ends of the shaft and thus gives unequal pressure at different points in the length of the cot against its opposing bottom roll, which makes unequal drafting action as the strand being drawn is traversed back and forth.

Hence, solid rolls have nearly always been employed where heavy weighting is compelled. in

the anti-friction type of construction.

The unavoidable bending of the shaft Just referred to, and caused by the established practice of applying the weighting load solely at midlength of the shaft between the two bosses, which results in throwing by far the major portion of the load onto the inward one of the two ball bearings customarilyv employed to support each shell roll, is a drawback present in this type of anti-' friction rolls regardless of the weighting, differing only in degree as the weighting is increased This causes the inner bearing of each shell roll to fail long before the outer one is impaired through use, the two bearings being conventionally made alike and of the maximum size allowed by the space limitations referred to within the shell roll. This unequal loading and increased wear of the inner bearings is enhanced in the case of long rolls.

To overcome these obstacles which have prevented the adoption of anti-friction typetop rolls where heavy weighting is required, and also to. lengthen the life of such top rolls even where light weighting is employed, according to the invention the inward anti-friction bearing of each shell roll 'is removed from its previous position' within the shell roll and within the length of the working surface of the cot, and instead is applied to the inward end of the shell roll as in effect an extension thereof. Thus released from its con-' finement within the shell roll, a much larger bearing can be used for the support of the shell roll without increasing the overall diameter of the cots surface or reducing the thickness of the cat's walls; such enlarged bearings have greater load-carrying capacity than could be achieved by any similar bearing positioned within the length of the shell roll and its cot. Additionally, by thus moving the bearing out from within the cot and shell roll, it brought nearer to the point of application of the loading force, namely, the

weighting saddle, thus cutting down the leverage of the turning couple which causes deflection of the shaft from its straight and true relation. With the bending effort of the'shaft thus reduced, the outward end of each shell roll and its cot is held more closely in contact with its opposing lower roll; the tendency of any bending in the supporting shaft, as is well known, being to lift the outward end of the cot away from the lower roll, reducing the wanted pressure and adload is required for the particular drafting operation contemplated, as in worsted or wool drafting where heavy weight is required, the best that could be attainedwith prior constructions would be aroll capable of bearing a maximum practicable load of 30 lbs. on each boss,or a total of 60 lbs., even neglecting the overloading of the inward bearings which comes from the bending of the shaft; hence anti-friction shell type rolls could not be used in this situation. But through the use of the invention, an extension bearing of atleast 25' lbs. working capacity, and actually of far greater practicable capacity, can be installed in the extension at the inward end of each shell roll, whereby the load-bearing capacity of each boss is most simply raised to 40 lbs., or 80 lbs. for the entire roll, thus enabling the benefits of the anti-friction type top roll to be realized in this case. The only restriction on the diametrical width of the bearing in this extension is that imposed by the shape and size of the confronting portions of the lower roll.

Other objects of the invention, and the manner of their attainment, are as pointed out hereinafter.

Illustrative embodiments of the invention are shown in the accompanying drawings-in which Fig. 1 is an axial section of a portion of an anti-friction double boss top roll, showing both the extension bearing and the included bearing formed of separate elements applied to the respective ends of the shell roll.

Fig. 2 is a corresponding section of a portion of a similar r011 showing both the extension for the inward bearing and the ball-race of the outward bearing formed as integral parts of the shell roll.

The improved top roll of Fig. 1 comprises a shaft 1 and shell rolls 3 on which latter are adhesively fixed the cots 5. Each shell roll 3 and its cot 5 is mounted for free rotation about shaft I by means of anti-friction bearings, herein ball bearings indicated generally by the reference characters I and 9. The shell rolls and cots are retained in their desired. working positions lengthwise of the shaft i by sleeves ll fitting the plain portions of the reduced extremities l3 of the shaft and internally threaded to screw upon the threaded ends of portions l3 and be retained thereon in aixally adjusted position by grub screws l5 screwed in the outer ends of sleeves H and bearing against the ends of shaft I. Cooperating with the sleeves H, a spacer I! in the shape of a sleeve'freely slidable on shaft l is mounted between the adjacentends of the cones of inward bearings 9. This sleeve is equipped with annular ridges I3 to receive between them the saddle 2! of the weighting mechanism of the spinning or drawing frame in which the improved roll is to be used.

In this form of the invention, all parts of each bearing are made separate from the shell roll which they support. That is, each bearing assembly comprises a tubular portion 23, 24, having a reduced extremity which is pressed into operativcly fixed position within the extremity of shell roll 3, and having an interior bore of two different diameters joined by a beveled shoulder which latter constitutes the ball-race for the balls 25 and 26 of each inner and outer hearing. The cone 2T, 28, of each bearing fits closely but slidably upon shaft I, that at the outward end of the shell roll being held in adjusted position by engagement with sleeve H and that at the inward end by engagement with spacer I'I. As

heretofore, bearing I at the outward end of the shell roll lies wholly within the length of the fiber-engaging surface of the cot thereon.

In accordance with the invention, the bearing 9 at the inward end of each shell roll 3 has its load-bearing surfaces all located outside of and inwardly beyond the end of shell roll 3 and beyond the end of cot 5 and its fiber-engaging surface. This is accomplished in Fig. 1 by making its tubular member 23, in which is formed the ball-race, of an outer diameter substantially exceeding that of shell roll 3 and the inside diameter of the cot, but less than the outside diameter of the cot, affixing this portion to the end of shell roll 3 as described by press-fitting its reduced portion 23 within the end of shell roll 3. With its overall diameter thus increased well beyond the outside diameter of shell roll 3, the internal diameter and the ball race formed therein are likewise increased to or beyond the inside diameter of the cot to accommodate'balls 25 of greater diameter than those which can be used in an internally located bearing such as I, and a larger cone 2! suiting the larger balls is installed to support the latter about shaft l. Hence the bearing 9 thus formed as an'extension on the inward end of shell roll 3 has far greater load-bearing capacity by reason of its increased size, beyond any similar bearing which could be located within the bore of shell roll 3.

In the form of Fig. 2, the ball-races are integral with the shell rolls 3|, and the increased internal diameter of the ball-race of the inward hearing 33 is attained by making an extension 35 on the inward eri'd' of shell roll 3| which has an outside diameter greater than that of the cotsupporting surface 31 of such shell roll. Within this enlarged extension 35 is formed theballrace receiving balls 39 of the desired size for the load to be borne and substantially greater than the balls 4| of the outward bearing 43 which is located wholly within the end of shell roll 3| and within the length of the working surface of cot 45 mounted thereon. A cone l1 commensurate in load-bearing capacity with the enlarged balls 39 which it supports,'is slidablymounted on shaft 49 as hereinbefore. The respective cones or bearings 33 and 43 are held in fixed and adjusted position lengthwise of shaft 9 respectively by spacer 5| at mid-length of the shaft and sleeve 53 threaded on the reduced end portion 55 of the shaft and held thereon by grub screw 51.

While I have illustrated and described certain forms in which the invention may be embodied, I am aware that many modifications may be made therein by any person skilled in the art, without departing from the scope of the invention as expressed in the claims. Therefore, I do not wish to be limited to the particular forms shown or to the details of construction thereof but what I do claim is;

l. A top roll for fiber drawing mechanism having in combination a shaft, a shell roll encircling such shaft, ball bearings for such shell roll, a cot mounted on'such shell roll, the shell roll having a portion of greater external diameter than the inside of the cot but of lesser diameter than the outside of the cot, one of the ball bearings being located in such portion and having greater load-bearing capacity than the other bearing.

2. A top roll for fiber drawing mechanism having in combination a shaft, a shell roll. encircling such shaft, a cot mounted on such. shell roll, the

shell roll having at one end an extension of greater external diameter than the internal diameter of the cot, a ball bearing assembly within such extension supporting the shell roll for rotation about the shaft, and a second ball bearing assembly at the other end of the shell roll.

3. A top roll for fiber drawing mechanism having in combination a shaft, two shell rolls on such shaft, a cot on each shell roll, each shell roll having at its end nearest the other shell roll an extension of greater internal diameter than the internal diameter of its cot, a ball bearing assembly within each such extension, a second ball bearing assembly located inside the other end of each shell roll within the length of the cot thereon, such bearings supporting the shell rolls for rotation about the shaft.

4. A top roll for fiber drawing mechanism having in combination a shaft, two shell rolls encircling such shaft, means in connection with the shaft holding the shell rolls spaced apart leaving a space between them for weighting the shaft by roll-weighting means, a cot mounted on each shell roll, the proximate ends of the shell rolls each having an extension reaching beyond the end of the cot thereon, a ball bearing assembly of greater external diameter than the internal diameter of the cot located within such extension, and a second ball bearing assembly at the other end of each shell roll and within the length of the cot thereon.

5. In a top roll for fiber drawing mechanism, in combination, a shaft, a, cot, a shell roll on which the cot is mounted, ball bearings supporting the roll rctatably on the shaft, the shell roll having an extension beyond the end of the cot, and a ball-race formed in such extension for one of the bearings and having a maximum diameter greater than the internal diameter of the cot.

6. A top roll for fiber drawing mechanism having in combination a shaft, two shell rolls encircling the shaft, a cot mounted on each shell roll, a spacer on the shaft between the shell rolls adapted to receive weighting pressure for the top roll, a ball bearing assembly located at the outward end of each shell roll within the length of the cot thereon, and a ball bearing assembly comprising a cone, a ball race, and bearing balls supporting the inward end of each shell roll, such latter assembly having its ball race of greater diameter than the inside diameter of the said cot, located between the end of the cot and the spacer, and having greater load bearing capacity than the other ball bearing assembly of such shell roll.

RICHARDK. BUTLER,

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,484,045 Wardwell Feb. 19, 1924 2,267,443 Cobb Dec. 23, 1941 FOREIGN PATENTS Number Country Date 210,298 Great Britain Jan. :31, 1924 677,776 France Mar. 14, 1930 

